a disease caused by an uncontrolled division of abnormal cells in a part of the body

he's got cancer

lung cancer

an evil or destructive practice or phenomenon that is hard to contain or eradicate

gambling is a cancer sweeping across the nation

a constellation (the Crab), said to represent a crab crushed under the foot of Hercules. It contains the globular star cluster of Praesepe or the Beehive

the fourth sign of the zodiac, which the sun enters at the northern summer solstice (about 21 June)

a person born when the sun is in the sign of Cancer

used with preceding Greek letter or numeral to designate a star in the constellation Cancer

the star Delta Cancri